Aragon and Catalonia meet along the Segre and Ebro here, and the map is full of names that mean corners and nooks. The Sierra de los Rincones is a low range of dry, rocky hills above the confluence of the Segre, Cinca and Ebro rivers, with scrub of juniper, thyme and pine and a lot of bare ground, in a region that gets less than 400 millimetres of rain a year. The great reservoir of Mequinenza, the Mar de Aragón, lies to the south, and from the high ground the view takes in water, hills and a haze of dust. The Ebro here is more than a river, it is a reservoir, with the valley flooded and the old towns beneath the water.
Mequinenza was a mining town, which surprises people. The lignite seams under the hills were worked for coal, and the town's life revolved around the mines and the barges on the river. The coal has gone, and the mines are closed, but a museum recalls the work. The steppe birds are the quiet bonus, with larks, sandgrouse and the occasional bustard in the open scrub, and the sky here is huge.
Rock shelters in these hills belong to the family of Levantine paintings that UNESCO listed in 1998, with small red figures that may be thousands of years old. They are fragile and mostly unmarked, so ask in Fraga or Mequinenza for guidance and keep to any rules about access. A visit is more rewarding with a local guide than alone.
The riding is hot and dry, with roads running along the ridges and through the valleys with gentle curves, and you will be surprised how few cars you meet. Summers are scorching, so ride early, and winters can be cold and foggy. Fraga, with about 14,000 people 16 km away, is the nearest place with fuel, supermarkets and rooms. The local peaches and olive oil are good, and the reservoir attracts fishermen who come for the huge catfish. A coffee on the plaza in Fraga makes a good break.